Food Chain

A food chain is the sequential sequence of living organisms in an ecosystem where one organism consumes another to transfer food energy.

Grass (Primary) → Insects (Primary Consumer) → Thrush (Secondary Consumer) → Sparrow Hawk (Tertiary Consumer)

A food chain

1. Principle of Continuity: A complete food chain must begin with photosynthesis (energy capture) and end in decay (decomposition) – energy must be continuously supplied from outside (the sun) to sustain it.
2. Principle of Efficiency: Shorter food chains are more energy-efficient. Longer chains waste more energy at each transfer and are less stable.
3. Principle of the 10% Law: Only about 10% of energy is transferred from one trophic level to the next; the rest is lost as heat via respiration.

• A food chain is a linear sequence of living organisms in an ecosystem where food energy is transferred as one organism consumes another.
• The structural flow typically moves from primary producers to successive levels of consumers, such as from grass to insects, then to a thrush, and finally to a sparrow hawk.
• According to the principle of continuity, a complete food chain requires a continuous external energy supply, always beginning with photosynthesis and ending with decomposition.
• The principle of efficiency dictates that shorter food chains are more stable and energy-efficient because less energy is wasted across fewer transfers.
• Under the 10% law, only about 10% of the available energy is passed to the next trophic level, while the remainder is lost as heat through respiration.